SOUNAL O Rouede。 Routledge URBAN TECHNOLOGY Journal of Urban Technology ISSN:1063-0732(Print)1466-1853(Online)Journal homepage:http://www.tandfonline.com/loi/cjut20 The First Two Decades of Smart-City Research:A Bibliometric Analysis Luca Mora,Roberto Bolici Mark Deakin To cite this article:Luca Mora,Roberto Bolici Mark Deakin(2017)The First Two Decades of Smart-City Research:A Bibliometric Analysis,Journal of Urban Technology,24:1,3-27,DOI: 10.1080/10630732.2017.1285123 To link to this article:http://dx.doi.org/10.1080/10630732.2017.1285123 Published online:22 Mar 2017. Submit your article to this journal 山 Article views:388 a View related articles ① View Crossmark data☑ Citing articles:1View citing articles Full Terms Conditions of access and use can be found at http://www.tandfonline.com/action/journallnformation?journalCode=cjut20 Download by:[Shanghai Jiaotong University] Date:25 August 2017,At:03:36
Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=cjut20 Download by: [Shanghai Jiaotong University] Date: 25 August 2017, At: 03:36 Journal of Urban Technology ISSN: 1063-0732 (Print) 1466-1853 (Online) Journal homepage: http://www.tandfonline.com/loi/cjut20 The First Two Decades of Smart-City Research: A Bibliometric Analysis Luca Mora, Roberto Bolici & Mark Deakin To cite this article: Luca Mora, Roberto Bolici & Mark Deakin (2017) The First Two Decades of Smart-City Research: A Bibliometric Analysis, Journal of Urban Technology, 24:1, 3-27, DOI: 10.1080/10630732.2017.1285123 To link to this article: http://dx.doi.org/10.1080/10630732.2017.1285123 Published online: 22 Mar 2017. Submit your article to this journal Article views: 388 View related articles View Crossmark data Citing articles: 1 View citing articles
JOURNAL OF URBAN TECHNOLOGY,2017 V0L24,N0.1,3-27 Routledge http:/k.doi.org/10.1080/10630732.2017.1285123 Taylor Francis Group Check for updates The First Two Decades of Smart-City Research:A Bibliometric Analysis Luca Mora,Roberto Bolici and Mark Deakin aDepartment of Architecture,Built Environment and Construction Engineering,Politecnico di Milano,Milano, Italy;PDepartment of Architecture,Built Environment and Construction Engineering (ABC),Politecnico di Milano,Milan,Italy:School of Engineering and Built Environment,Edinburgh Napier University,Edinburgh, UK ABSTRACT KEYWORDS This paper reports on the first two decades of research on smart Smart-city research;urban cities by conducting a bibliometric analysis of the literature innovation;bibliometric published between 1992 and 2012.The analysis shows that smart- analysis;development paths; city research is fragmented and lacks cohesion,and its growth corporate model;holistic follows two main development paths.The first one is based on interpretation the peer-reviewed publications produced by European universities,which support a holistic perspective on smart cities. The second path,instead,stands on the gray literature produced by the American business community and relates to a techno- centric understanding of the subject.Divided along such paths, the future development of this new and promising field of research risks being undermined.For while the bibliometric analysis indicates that smart cities are emerging as a fast-growing topic of scientific enquiry,much of the knowledge that is SuojoeIf leyueyS] generated about them is singularly technological in nature.In that sense,lacking the social intelligence,cultural artifacts,and environmental attributes,which are needed for the ICT-related urban innovation that such research champions. 入Ko Introduction Cities are complex and highly organized systems,"a collection of elements that act inde- pendently of one another but nevertheless manage to act in concert."Their state of balance is extremely sensitive and subject to continuous changes dependent on"how we intervene in their organization through different forms of planning"(Batty and Marshall,2009:567). The need to manage this difficult scenario has required the connection of many academic disciplines (Benevolo,2011;Secchi,2011)brought together in the unique field of urban studies (Liu,2005),which is "one of the longest established interdisciplinary fields within the modern academy"(Kamalski and Kirby,2012:S3). Computer science is one of these disciplines,and its continuous and progressive approach to urban studies started during the last years of the twentieth century,when CONTACT Luca Mora luca.mora@polimi.it Politecnico di Milano,Department of Architecture,Built Environment and Construction Engineering,Via G.Ponzio 31,20133 Milano,Italy 2017 The Society of Urban Technology
The First Two Decades of Smart-City Research: A Bibliometric Analysis Luca Moraa , Roberto Bolicib and Mark Deakinc a Department of Architecture, Built Environment and Construction Engineering, Politecnico di Milano, Milano, Italy; b Department of Architecture, Built Environment and Construction Engineering (ABC), Politecnico di Milano, Milan, Italy; c School of Engineering and Built Environment, Edinburgh Napier University, Edinburgh, UK ABSTRACT This paper reports on the first two decades of research on smart cities by conducting a bibliometric analysis of the literature published between 1992 and 2012. The analysis shows that smartcity research is fragmented and lacks cohesion, and its growth follows two main development paths. The first one is based on the peer-reviewed publications produced by European universities, which support a holistic perspective on smart cities. The second path, instead, stands on the gray literature produced by the American business community and relates to a technocentric understanding of the subject. Divided along such paths, the future development of this new and promising field of research risks being undermined. For while the bibliometric analysis indicates that smart cities are emerging as a fast-growing topic of scientific enquiry, much of the knowledge that is generated about them is singularly technological in nature. In that sense, lacking the social intelligence, cultural artifacts, and environmental attributes, which are needed for the ICT-related urban innovation that such research champions. KEYWORDS Smart-city research; urban innovation; bibliometric analysis; development paths; corporate model; holistic interpretation Introduction Cities are complex and highly organized systems, “a collection of elements that act independently of one another but nevertheless manage to act in concert.” Their state of balance is extremely sensitive and subject to continuous changes dependent on “how we intervene in their organization through different forms of planning” (Batty and Marshall, 2009: 567). The need to manage this difficult scenario has required the connection of many academic disciplines (Benevolo, 2011; Secchi, 2011) brought together in the unique field of urban studies (Liu, 2005), which is “one of the longest established interdisciplinary fields within the modern academy” (Kamalski and Kirby, 2012: S3). Computer science is one of these disciplines, and its continuous and progressive approach to urban studies started during the last years of the twentieth century, when © 2017 The Society of Urban Technology CONTACT Luca Mora luca.mora@polimi.it Politecnico di Milano, Department of Architecture, Built Environment and Construction Engineering, Via G. Ponzio 31, 20133 Milano, Italy JOURNAL OF URBAN TECHNOLOGY, 2017 VOL. 24, NO. 1, 3–27 http://dx.doi.org/10.1080/10630732.2017.1285123 Downloaded by [Shanghai Jiaotong University] at 03:36 25 August 2017
4©L.MORA ET AL the digital revolution began to transform urban areas"into a constellation of computers" (Batty,1997:155).During this period, many commentators seemed to suggest that the new frontier [of information technology]was to provide solutions for overcoming most spatial and social problems [and]cities looked like the ideal arena where this revolution would test and show itself,changing economic devel- opment,services,and above all,community life.(Firmino,2003:3) In this scenario,the information and communication technologies (ICTs)of urban areas are innovations supporting a new science of cities(Batty,2014). The exploration of the relationship between ICTs and urban areas began with Graham and Marvin's Telecommunications and the City (Graham and Marvin,1996). Along with the work produced by Mitchell (1995,1999,2003)and Castells (1996), their research activity allowed this new area of knowledge to take shape and develop in a concrete form.This process of knowledge production resulted in the publication isnany of numerous scientific documents (see Graham and Marvin 1996,1999,2001,2004; Graham 1997,2000,2001,2002,2004a).Many of these publications can be considered 9 the most influential resources in the cognitive structure of"urban ICT studies"(Graham, 2004b:3),a sub-discipline of urban studies in which research is carried out to study "the 8.501m complex and poorly understood set of relationships between telecommunications and the development,planning and management of contemporary cities"(Graham and Marvin,1996:XIII). As an object of scientific enquiry,smart city studies fall in this research domain and first appeared in 1992 within the book entitled The Technopolis Phenomenon:Smart Cities,Fast Systems,Global Networks (Gibson et al.,1992).Over the years,smart cities have become the symbol of ICT-driven urban innovation and development and have attracted the uooef eyueyS] increasing attention of researchers from universities,governments,and businesses. Thanks to their interest,smart-city research has grown sharply.Evidence of this trend can be found by analyzing Google Scholar's data.Following a request to identify the lit- erature produced between 1992 and 2015 in which the term "smart city"is included in the singular or plural form,the scholarly engine developed by Google has sourced 合 25,770 documents.'Data shows that the annual production of publications on smart apeojuM cities has increased by 600 times within 24 years,moving from 16 in 1992 to 9,494 in 20152 The exploratory study reported on in this paper aims to provide an overall and detailed picture of what happened during the first two decades of research on smart cities,and lead to an improved understanding of the origins and progressive evolution of this fast- emerging research area and its intellectual structure.This aim is achieved by answering the following research questions: What are the characteristics of the literature produced during the period 1992 to 2012 in terms of type,influence,and impact? How large was the scientific community researching smart cities? What are the influence and productivity levels of researchers falling within this commu- nity and the organizations to which they belong? What is the interpretation of the smart-city concept that emerges from their research?
the digital revolution began to transform urban areas “into a constellation of computers” (Batty, 1997: 155). During this period, many commentators seemed to suggest that the new frontier [of information technology] was to provide solutions for overcoming most spatial and social problems [and] cities looked like the ideal arena where this revolution would test and show itself, changing economic development, services, and above all, community life. (Firmino, 2003: 3) In this scenario, the information and communication technologies (ICTs) of urban areas are innovations supporting a new science of cities (Batty, 2014). The exploration of the relationship between ICTs and urban areas began with Graham and Marvin’s Telecommunications and the City (Graham and Marvin, 1996). Along with the work produced by Mitchell (1995, 1999, 2003) and Castells (1996), their research activity allowed this new area of knowledge to take shape and develop in a concrete form. This process of knowledge production resulted in the publication of numerous scientific documents (see Graham and Marvin 1996, 1999, 2001, 2004; Graham 1997, 2000, 2001, 2002, 2004a). Many of these publications can be considered the most influential resources in the cognitive structure of “urban ICT studies” (Graham, 2004b: 3), a sub-discipline of urban studies in which research is carried out to study “the complex and poorly understood set of relationships between telecommunications and the development, planning and management of contemporary cities” (Graham and Marvin, 1996: XIII). As an object of scientific enquiry, smart city studies fall in this research domain and first appeared in 1992 within the book entitled The Technopolis Phenomenon: Smart Cities, Fast Systems, Global Networks (Gibson et al., 1992). Over the years, smart cities have become the symbol of ICT-driven urban innovation and development and have attracted the increasing attention of researchers from universities, governments, and businesses. Thanks to their interest, smart-city research has grown sharply. Evidence of this trend can be found by analyzing Google Scholar’s data. Following a request to identify the literature produced between 1992 and 2015 in which the term “smart city” is included in the singular or plural form, the scholarly engine developed by Google has sourced 25,770 documents.1 Data shows that the annual production of publications on smart cities has increased by 600 times within 24 years, moving from 16 in 1992 to 9,494 in 2015.2 The exploratory study reported on in this paper aims to provide an overall and detailed picture of what happened during the first two decades of research on smart cities, and lead to an improved understanding of the origins and progressive evolution of this fastemerging research area and its intellectual structure. This aim is achieved by answering the following research questions: . What are the characteristics of the literature produced during the period 1992 to 2012 in terms of type, influence, and impact? . How large was the scientific community researching smart cities? . What are the influence and productivity levels of researchers falling within this community and the organizations to which they belong? . What is the interpretation of the smart-city concept that emerges from their research? 4 L. MORA ET AL. Downloaded by [Shanghai Jiaotong University] at 03:36 25 August 2017
JOURNAL OF URBAN TECHNOLOGY5 What factors have influenced the development of the intellectual structure resulting from the first two decades of smart-city research? To answer these questions,we used bibliometric analysis techniques to analyze both the literature on smart cities published between 1992 and 2012,and the community ofresearch- ers involved in its production.The methodology used to perform the analysis is illustrated in the next section of the paper.This is followed by an in-depth description of the findings which sheds light on the first 20 years of research in the field of smart cities.In another section,we discuss the findings in relation to the content of the smart-city literature pro- duced subsequent to the period under investigation.The paper concludes with some rec- ommendations aimed at guiding future research on smart cities in line with our findings. isnany Bibliometrics and the Analysis of Knowledge Domains Bibliometrics investigates the formal properties of knowledge domains by using math- 9 ematical and statistical methods (Pritchard,1969;Ding et al.,2001;Godin,2006;De Bellis,2009).Interest in applying these methods to explore the development of smart cities as a knowledge domain has grown considerably over the past five years and has resulted in the production of the following publications: Duran-Sanchez et al.,2017:a description of scientific research on smart cities by way of a bibliometric analysis and through a review of the literature indexed in Web of Science and Elsevier's Scopus databases uoloelf eyueyS] Ojo et al.,2016:an examination of the smart-city knowledge domain using Scopus' journal articles and conference papers related to both smart cities and intelligent cities,which we consider equivalent terms Tregua et al.,2015:an analysis of the relationship between sustainable and smart cities using 367 journal articles and books indexed in Web of Science 名 Ricciardi and za.2015:an examination of about 100 documents stored in the websites of two international conferences on smart cities "to define the boundaries of smart city apeojumo research and to draw a map of [its]interdisciplinary community"(163). de Jong et al.,2015:an identification of the conceptual differences and relationships between twelve dominant city categories(sustainable city,eco city,low carbon city,live- able city,green city,smart city,digital city,ubiquitous city,intelligent city,information city,knowledge city,resilient city).This study is conducted by way of a bibliometric analysis and through the academic literature retrieved from Web of Science and Scopus. What these studies have in common is a tendency to focus on specific aspects of smart cities,or compare them to other different city categories rather than capturing an overall picture of smart-city research.Moreover,they generally conduct bibliometric analyses that are sourced from a limited number of publications and databases in which gray literature is not indexed (Hutton,2009).Therefore,some relevant source documents may have been missed. The bibliometric study of this paper aims to overcome the limitations of existing bib- liometric analyses into smart cities by:
. What factors have influenced the development of the intellectual structure resulting from the first two decades of smart-city research? To answer these questions, we used bibliometric analysis techniques to analyze both the literature on smart cities published between 1992 and 2012, and the community of researchers involved in its production. The methodology used to perform the analysis is illustrated in the next section of the paper. This is followed by an in-depth description of the findings which sheds light on the first 20 years of research in the field of smart cities. In another section, we discuss the findings in relation to the content of the smart-city literature produced subsequent to the period under investigation. The paper concludes with some recommendations aimed at guiding future research on smart cities in line with our findings. Bibliometrics and the Analysis of Knowledge Domains Bibliometrics investigates the formal properties of knowledge domains by using mathematical and statistical methods (Pritchard, 1969; Ding et al., 2001; Godin, 2006; De Bellis, 2009). Interest in applying these methods to explore the development of smart cities as a knowledge domain has grown considerably over the past five years and has resulted in the production of the following publications: . Durán-Sánchez et al., 2017: a description of scientific research on smart cities by way of a bibliometric analysis and through a review of the literature indexed in Web of Science and Elsevier’s Scopus databases . Ojo et al., 2016: an examination of the smart-city knowledge domain using Scopus’ journal articles and conference papers related to both smart cities and intelligent cities, which we consider equivalent terms . Tregua et al., 2015: an analysis of the relationship between sustainable and smart cities using 367 journal articles and books indexed in Web of Science . Ricciardi and Za, 2015: an examination of about 100 documents stored in the websites of two international conferences on smart cities “to define the boundaries of smart city research and to draw a map of [its] interdisciplinary community” (163). . de Jong et al., 2015: an identification of the conceptual differences and relationships between twelve dominant city categories (sustainable city, eco city, low carbon city, liveable city, green city, smart city, digital city, ubiquitous city, intelligent city, information city, knowledge city, resilient city). This study is conducted by way of a bibliometric analysis and through the academic literature retrieved from Web of Science and Scopus. What these studies have in common is a tendency to focus on specific aspects of smart cities, or compare them to other different city categories rather than capturing an overall picture of smart-city research. Moreover, they generally conduct bibliometric analyses that are sourced from a limited number of publications and databases in which gray literature is not indexed (Hutton, 2009). Therefore, some relevant source documents may have been missed. The bibliometric study of this paper aims to overcome the limitations of existing bibliometric analyses into smart cities by: JOURNAL OF URBAN TECHNOLOGY 5 Downloaded by [Shanghai Jiaotong University] at 03:36 25 August 2017
6⊙L.MORA ET AL focusing only on the overall intellectual structure of this knowledge domain expanding the number of databases used to source documents3 including both academic publications and gray literature. This bibliometric study used 1,067 source documents identified with a keyword search and combining the analysis of the citations between them,together with citation and pub- lication counts,which are the two most basic bibliometric measures (Tijssen and van Leeuwen,2003;Martin and Daim,2008).These documents represent all the smart-city lit- erature published in the English language between 1992 and 2012.More specifically,that English language literature containing the term“smart city”or the term“smart cities,”in the title,abstract,keyword list,or body of the text,and stored in the following scholarly databases:Google Scholar;ISI Web of Science;IEEE Xplore;Scopus;SpringerLink; Engineering Village;ScienceDirect;and Taylor and Francis Online. The use of multiple databases made it possible to conduct a comprehensive interdisci- isnany plinary search and broaden the field of investigation,avoiding the risk of not capturing the full extent of research on smart cities.However,it is important to note that this choice was 9 particularly challenging and time consuming because the initial number of publications identified with the keyword search was 9,799.To extract the list of source documents, each publication was included in a single dataset and checked to correct typographical errors in the titles,authors'names,or publication dates.Repeated documents that were found in more than one database were eliminated.Finally,the title,abstract,keyword list,and body of the text of each remaining publication was manually examined to verify the effective presence of the keyword.Documents in which this search was shown to be negative were eliminated. After completing the search phase,the source documents were cataloged considering their type:abstracts,editorials,journal articles,books,book chapters,conference papers,and gray literature(See Figure 1).The last category includes the documents gen- erally defined as gray and represents a substantial part of the scientific production, especially in recent years(Schopfel and Farace,2010).According to the most common 五 definition,gray literature represents the literature that is"produced on all levels of govern- ment,academics,business and industry in print and electronic formats,but [...not con- apeoluMo trolled by commercial publishers,i.e.where publishing is not the primary activity of the producing body"(Schopfel,2010:12). All source documents were then linked to authors by their full names and the organ- izations they represent.Details about organizations were found by searching their official websites,the source documents,and the databases used for the keyword search.In this study,the most recent affiliation was attributed to each author.During this activity, data on both the type and location of each organization was also collected(See Figure 2).Based on types,four main categories were identified:(1)research and education:uni- versities,academies,and colleges;(2)research and business:private companies operating in the ICT sector which are involved in research and consultancy activities or in the dis- tribution of goods and services;(3)research and government:public authorities and their research institutes);(4)other.In case of organizations operating in multiple locations,the main headquarters were considered. Finally,before starting the analysis,citation data were extracted manually from the list of references included in each source document.In addition,considering that citation data
. focusing only on the overall intellectual structure of this knowledge domain . expanding the number of databases used to source documents3 . including both academic publications and gray literature. This bibliometric study used 1,067 source documents identified with a keyword search and combining the analysis of the citations between them, together with citation and publication counts, which are the two most basic bibliometric measures (Tijssen and van Leeuwen, 2003; Martin and Daim, 2008). These documents represent all the smart-city literature published in the English language between 1992 and 2012. More specifically, that English language literature containing the term “smart city” or the term “smart cities,” in the title, abstract, keyword list, or body of the text, and stored in the following scholarly databases:4 Google Scholar; ISI Web of Science; IEEE Xplore; Scopus; SpringerLink; Engineering Village; ScienceDirect; and Taylor and Francis Online.5 The use of multiple databases made it possible to conduct a comprehensive interdisciplinary search and broaden the field of investigation, avoiding the risk of not capturing the full extent of research on smart cities. However, it is important to note that this choice was particularly challenging and time consuming because the initial number of publications identified with the keyword search was 9,799. To extract the list of source documents, each publication was included in a single dataset and checked to correct typographical errors in the titles, authors’ names, or publication dates. Repeated documents that were found in more than one database were eliminated. Finally, the title, abstract, keyword list, and body of the text of each remaining publication was manually examined to verify the effective presence of the keyword. Documents in which this search was shown to be negative were eliminated. After completing the search phase, the source documents were cataloged considering their type: abstracts, editorials, journal articles, books, book chapters, conference papers,6 and gray literature7 (See Figure 1). The last category includes the documents generally defined as gray and represents a substantial part of the scientific production, especially in recent years (Schopfel and Farace, 2010). According to the most common definition, gray literature represents the literature that is “produced on all levels of government, academics, business and industry in print and electronic formats, but […] not controlled by commercial publishers, i.e. where publishing is not the primary activity of the producing body” (Schopfel, 2010: 12). All source documents were then linked to authors by their full names and the organizations they represent. Details about organizations were found by searching their official websites, the source documents, and the databases used for the keyword search. In this study, the most recent affiliation was attributed to each author. During this activity, data on both the type and location of each organization was also collected (See Figure 2). Based on types, four main categories were identified: (1) research and education: universities, academies, and colleges; (2) research and business: private companies operating in the ICT sector which are involved in research and consultancy activities or in the distribution of goods and services; (3) research and government: public authorities and their research institutes); (4) other. In case of organizations operating in multiple locations, the main headquarters were considered. Finally, before starting the analysis, citation data were extracted manually from the list of references included in each source document. In addition, considering that citation data 6 L. MORA ET AL. Downloaded by [Shanghai Jiaotong University] at 03:36 25 August 2017
JOURNAL OF URBAN TECHNOLOGY7 Period11992-2006 ，Period22007-20091 Period3(2010-2012 385 356 350 315 280 : 27H 245 213 210 175 140 LIO7 1sn3nV St 9:E0e [AlSJaAlun Suojoelf leyaueys] 105 70 59 33 35 24-25 2522 9 0200 030 8 Ab Bo Ch Ed Ar Co Gr:Ab Bo Ch Ed Ar Co Gr:Ab Bo Ch Ed Ar Co Gr Ab Abstract Bo Book Ch Book chapter Ed Editorial: Ar Journal article;Co Conference paper,Gr Grey literature Figure 1.Source documents by type and period of publication often contain errors,which can lead to significant variations in the results of their analysis (Adam,2002),all citations were tested for correctness and completeness,so as to guaran- tee the highest degree of data reliability.Altogether,a total of 22,137 citations were col- 花o P lected(957 to source documents and 21,180 to non-source documents),and they were used to build a frequency table showing each cited publication,together with the number of times it had been cited.This made it possible to determine that the total number of cited references was 17,574.Only citations to source documents were con- sidered during the analysis. The First Two Decades of Smart-City Research A New and Fast Growing Research Area The analysis shows that smart city-research established itself as a new area of scientific enquiry in 2009,and since then,it has been fast-growing,arousing strong interest from an expanding scientific community of researchers.This growth is particularly evident when observing the rise in the production of source documents(See Figure 3),which has continued to increase over time,together with the number of researchers involved
often contain errors, which can lead to significant variations in the results of their analysis (Adam, 2002), all citations were tested for correctness and completeness, so as to guarantee the highest degree of data reliability. Altogether, a total of 22,137 citations were collected (957 to source documents and 21,180 to non-source documents), and they were used to build a frequency table showing each cited publication, together with the number of times it had been cited. This made it possible to determine that the total number of cited references was 17,574. Only citations to source documents were considered during the analysis. The First Two Decades of Smart-City Research A New and Fast Growing Research Area The analysis shows that smart city-research established itself as a new area of scientific enquiry in 2009, and since then, it has been fast-growing, arousing strong interest from an expanding scientific community of researchers. This growth is particularly evident when observing the rise in the production of source documents (See Figure 3), which has continued to increase over time, together with the number of researchers involved Figure 1. Source documents by type and period of publication JOURNAL OF URBAN TECHNOLOGY 7 Downloaded by [Shanghai Jiaotong University] at 03:36 25 August 2017
8©L.MORA ET AL Africa (19)America(133),Asia (188),Australia (35).Europe (404) 275 250 237 225 200 175 150 137 125 100 83 LI07 1sn3nV St 9:E0e [ASJaAlun Suojoelf leyueys]Kq papeojuMod 75 53 50 33 26 25 25 25 16 10 15 0 uEdoBu EdGotBu EdGoBuEdo Ed ot B Research and Business;E Research and Education; G Research and Government O Other Figure 2.Organizations by type and location in their development(See Figure 4).Initially,this research area was very small,with only 19 source documents published during the first 10 years of research.Over the following eight years,from the beginning of 2002 to the end of 2009,production increased slightly. During this period 132 documents were published,about 17 per year.The period between 2010 and 2012,instead,was characterized by a tremendous growth in the number of pub- lications.More than 900 new source documents were produced in three years,and they represent approximately 86 percent of the smart-city literature developed during the first two decades of research. Fragmentation of Knowledge All branches of knowledge are composed of large groups of interconnected publications, and their structure can be represented through the use of complex mapping techniques, allowing the scientific community involved in their production to easily grasp "the big picture"(Moya-Anegon et al.,2004):"a spatial representation of the relationship among [...individual papers as reflected in some formal,strictly quantifiable properties of scientific literature at a given time"(De Bellis,2009:142).Citations are the elements that
in their development (See Figure 4). Initially, this research area was very small, with only 19 source documents published during the first 10 years of research. Over the following eight years, from the beginning of 2002 to the end of 2009, production increased slightly. During this period 132 documents were published, about 17 per year. The period between 2010 and 2012, instead, was characterized by a tremendous growth in the number of publications. More than 900 new source documents were produced in three years, and they represent approximately 86 percent of the smart-city literature developed during the first two decades of research. Fragmentation of Knowledge All branches of knowledge are composed of large groups of interconnected publications, and their structure can be represented through the use of complex mapping techniques, allowing the scientific community involved in their production to easily grasp “the big picture” (Moya-Anegon et al., 2004): “a spatial representation of the relationship among […] individual papers as reflected in some formal, strictly quantifiable properties of scientific literature at a given time” (De Bellis, 2009: 142). Citations are the elements that Figure 2. Organizations by type and location 8 L. MORA ET AL. Downloaded by [Shanghai Jiaotong University] at 03:36 25 August 2017
JOURNAL OF URBAN TECHNOLOGY 9 1100 1000 1source documents which belong to the smart city research field 900 %produced un the period 19922009 percentage of source documents 800 5%produced in the perod 2010-2012 percentage of source documents 700 600 500 400 LIOZ isnanV st 96:E0 e [AlIsJaalun 300 200 100 0- TT 含昌香台驾含器器号是尾第葛美号爱司美 Figure 3.Cumulative growth in the number of source documents uoloef eyueyS] create the connections between publications.They represent"a type of symbolic currency that signals intellectual influences"and serve as an indicator by which the influence and impact of any scientific document can be assessed (Jacobsen et al.,2013:226).By using citations,researchers can incorporate intellectual work from other research into their own studies (Garfield,1970;Small 1973,1978),and collaborate in the construction of 花o P the intellectual structure of their field of investigation. The use of these techniques made it possible to visualize the overall intellectual struc- ture that results from the first 20 years of research in the field of smart cities.The structure is illustrated in Figure 5,and is represented by a network of undirected and unweighted links in which the 1,067 source documents are nodes and the 957 citations referring to them are the connecting elements.This graph has been obtained using the Fruchter- man-Reingold layout algorithm provided by the open-source software Gephi(Fruchter- man and Reingold,1991).Within the graph,the source documents are represented by a circle with a diameter proportional to the number of citations they have received.There- fore,the larger the circle,the greater number of citations.In addition,source documents with at least one citation are shown in blue,whereas those without citations are gray. By observing the organization of the nodes,it becomes evident that fragmentation and divergence are the main features of this structure,and they result from the absence of con- nections between the source documents.This means that the impressive growth of avail- able scientific literature observed in the last three years of the second decade goes hand in
create the connections between publications. They represent “a type of symbolic currency that signals intellectual influences” and serve as an indicator by which the influence and impact of any scientific document can be assessed (Jacobsen et al., 2013: 226). By using citations, researchers can incorporate intellectual work from other research into their own studies (Garfield, 1970; Small 1973, 1978), and collaborate in the construction of the intellectual structure of their field of investigation. The use of these techniques made it possible to visualize the overall intellectual structure that results from the first 20 years of research in the field of smart cities. The structure is illustrated in Figure 5, and is represented by a network of undirected and unweighted links in which the 1,067 source documents are nodes and the 957 citations referring to them are the connecting elements. This graph has been obtained using the Fruchterman-Reingold layout algorithm provided by the open-source software Gephi (Fruchterman and Reingold, 1991). Within the graph, the source documents are represented by a circle with a diameter proportional to the number of citations they have received. Therefore, the larger the circle, the greater number of citations. In addition, source documents with at least one citation are shown in blue, whereas those without citations are gray. By observing the organization of the nodes, it becomes evident that fragmentation and divergence are the main features of this structure, and they result from the absence of connections between the source documents. This means that the impressive growth of available scientific literature observed in the last three years of the second decade goes hand in Figure 3. Cumulative growth in the number of source documents JOURNAL OF URBAN TECHNOLOGY 9 Downloaded by [Shanghai Jiaotong University] at 03:36 25 August 2017
10© L.MORA ET AL 2750 2500 2584authors involved in the F production of source documents 2250 %towork bewteen 1992 and 2009 percentage of authors who started 2000 88.89%68 petween2609and202 percentage of authors who started 1750 1500 1250 1000 750 LI07 1sn3nV St 9:E0e [ASJaAlun SuoloeIf leyueys]Kq papeojumod 500 250 0-一 Figure 4.Cumulative growth in the number of authors involved in the production of source documents hand with the lack of cohesion between the researchers involved in their production.As a result,the intellectual structure of the smart-city research area is divided into a multitude of unconnected publications.The central core of the network,indeed,is compact and well- 40 ●NODE TY1- ●oont3 oa Figure 5.Knowledge structure of the smart-city research field
hand with the lack of cohesion between the researchers involved in their production. As a result, the intellectual structure of the smart-city research area is divided into a multitude of unconnected publications. The central core of the network, indeed, is compact and wellFigure 4. Cumulative growth in the number of authors involved in the production of source documents Figure 5. Knowledge structure of the smart-city research field 10 L. MORA ET AL. Downloaded by [Shanghai Jiaotong University] at 03:36 25 August 2017
JOURNAL OF URBAN TECHNOLOGY 11 articulated thanks to the presence of citations,which indicate an active exchange of knowl- edge among researchers.However,moving towards the outer perimeter,the organization of the network changes completely.Source documents are disconnected or combined in groups that are small in number and detached from the main core. The Divergent Roots of Smart Cities Divergence,lack of cohesion,and limited intellectual exchange among researchers become even more evident when trying to find out a commonly accepted interpretation of smart cities,which is missing.This absence is highlighted in various source documents,such as those produced by Alkandari et al.(2012),Chourabi et al.(2012),Hollands (2008),and Paskaleva(2011).Many definitions of the smart city are provided in scholarly literature and they overlap one another,making it difficult to obtain a common understanding and agreement as to what it means.To illustrate this trend,some of these definitions snany have been extracted from the source documents and reported in Table 1. Table 1.Some definitions of smart cities extracted from the source documents SOURCE DOCUMENT DEFINITION Hall et al.(2000) "[The smart city is]the urban center of the future,made safe,secure environmentally green and efficient because all structures--whether for power,water,transportation,etc.are designed,constructed,and maintained making use of advanced,integrated materials, sensors,electronics,and networks which are interfaced with computerized systems comprised of databases,tracking,and decision-making algorithms" Odendaal (2003) "A smart city [...is one that capitalizes on the opportunities presented by Information and Communication Technology(ICT)in promoting its prosperity and influence" Partridge (2004) "A smart city is [a city that]actively embraces new technologies [seeking]to be a more open society where technology makes easier for people to have their say,gain access to services and to stay in touch with what is happening around them,simply and cheaply" Giffinger et al.(2007) "A Smart City is a city well performing in a forward-looking way in [..six characteristics [.. built on the 'smart'combination of endowments and activities of self-decisive,independent and aware citizens" Caragliu et al.(2009) "The concept of the 'smart city'has recently been introduced as a strategic device to encompass modern urban production factors in a common framework and,in particular,to highlight the importance of Information and Communication Technologies(ICTs)in the last 五 20 years for enhancing the competitive profile of a city" Paskaleva (2009) "In the context of the present study,the smart city is defined as one that takes advantages of apeojuM the opportunities offered by ICT in increasing local prosperity and competitiveness-an approach that implies integrated urban development involving multi-actor,multi-sector and multi-level perspectives" Belissent et al.(2010) "Forrester defines the smart city as [..a'city that uses information and communications technologies to make the critical infrastructure components and services of a city-- administration,education,healthcare,public safety,real estate,transportation,and utilities--more aware,interactive,and efficient" Hernandez-Munoz et al. "Smart Cities can represent an extraordinary rich ecosystem to promote the generation of (2011) massive deployments of city-scale applications and services for a large number of activity sectors" Alkandari et al.(2012) "A smart city is one that uses a smart system characterized by the interaction between infrastructure,capital,behaviours and cultures,achieved through their integration" Lazaroiu and Roscia "A new city model,called "the smart city",which represents a community of average (2012) technology size,interconnected and sustainable,comfortable,attractive and secure" Schaffers et al.(2012) "The smart city concept is multi-dimensional.It is a future scenario (what to achieve),even more it is an urban development strategy (how to achieve it).It focuses on how (Internet- related)technologies enhance the lives of citizens [..The smart city is about how people are empowered,through using technology,for contributing to urban change and realizing their ambitions.The smart city provides the conditions and resources for change.In this sense,the smart city is an urban laboratory,an urban innovation ecosystem,a living lab,an agent of change
articulated thanks to the presence of citations, which indicate an active exchange of knowledge among researchers. However, moving towards the outer perimeter, the organization of the network changes completely. Source documents are disconnected or combined in groups that are small in number and detached from the main core. The Divergent Roots of Smart Cities Divergence, lack of cohesion, and limited intellectual exchange among researchers become even more evident when trying to find out a commonly accepted interpretation of smart cities, which is missing. This absence is highlighted in various source documents, such as those produced by Alkandari et al. (2012), Chourabi et al. (2012), Hollands (2008), and Paskaleva (2011). Many definitions of the smart city are provided in scholarly literature and they overlap one another, making it difficult to obtain a common understanding and agreement as to what it means. To illustrate this trend, some of these definitions have been extracted from the source documents and reported in Table 1. Table 1. Some definitions of smart cities extracted from the source documents SOURCE DOCUMENT DEFINITION Hall et al. (2000) “[The smart city is] the urban center of the future, made safe, secure environmentally green, and efficient because all structures––whether for power, water, transportation, etc. are designed, constructed, and maintained making use of advanced, integrated materials, sensors, electronics, and networks which are interfaced with computerized systems comprised of databases, tracking, and decision-making algorithms” Odendaal (2003) “A smart city […] is one that capitalizes on the opportunities presented by Information and Communication Technology (ICT) in promoting its prosperity and influence” Partridge (2004) “A smart city is [a city that] actively embraces new technologies [seeking] to be a more open society where technology makes easier for people to have their say, gain access to services and to stay in touch with what is happening around them, simply and cheaply” Giffinger et al. (2007) “A Smart City is a city well performing in a forward-looking way in […] six characteristics […], built on the ‘smart’ combination of endowments and activities of self-decisive, independent and aware citizens” Caragliu et al. (2009) “The concept of the ‘smart city’ has recently been introduced as a strategic device to encompass modern urban production factors in a common framework and, in particular, to highlight the importance of Information and Communication Technologies (ICTs) in the last 20 years for enhancing the competitive profile of a city” Paskaleva (2009) “In the context of the present study, the smart city is defined as one that takes advantages of the opportunities offered by ICT in increasing local prosperity and competitiveness––an approach that implies integrated urban development involving multi-actor, multi-sector and multi-level perspectives” Belissent et al. (2010) “Forrester defines the smart city as […] a ‘city’ that uses information and communications technologies to make the critical infrastructure components and services of a city–– administration, education, healthcare, public safety, real estate, transportation, and utilities––more aware, interactive, and efficient” Hernández-Muñoz et al. (2011) “Smart Cities can represent an extraordinary rich ecosystem to promote the generation of massive deployments of city-scale applications and services for a large number of activity sectors” Alkandari et al. (2012) “A smart city is one that uses a smart system characterized by the interaction between infrastructure, capital, behaviours and cultures, achieved through their integration” Lazaroiu and Roscia (2012) “A new city model, called “the smart city”, which represents a community of average technology size, interconnected and sustainable, comfortable, attractive and secure” Schaffers et al. (2012) “The smart city concept is multi-dimensional. It is a future scenario (what to achieve), even more it is an urban development strategy (how to achieve it). It focuses on how (Internetrelated) technologies enhance the lives of citizens […] The smart city is about how people are empowered, through using technology, for contributing to urban change and realizing their ambitions. The smart city provides the conditions and resources for change. In this sense, the smart city is an urban laboratory, an urban innovation ecosystem, a living lab, an agent of change” JOURNAL OF URBAN TECHNOLOGY 11 Downloaded by [Shanghai Jiaotong University] at 03:36 25 August 2017
